Directional drilling tool



June-23, 1959 J. s. PAGE, s/R., ETAL DIRECTIONAL DRILLINGwooI.A

5 Sheets-Sheet 1 Filed May 2, 1955 June 23, 1959 J. S. PAGE, SR., ETAL DIRECTIONAL DRILLING TOOL 5 Sheets-Sheet 3 Filed May 2, 1955 June 23, 1959 J. s. PAGE, sR., ETA. 2,891,769

DIRECTIONAL DRILLING TOOL Filed May 2. 1955 S'Shets-Sheet 4 XR MN I WM5/7M SSheets-Sheet 5 June 23, 1959 J. S. PAGE, SR., ETAL DIRECTIONAL DRILLING TOOL Filed May 2. 1955 United States Patent C f DIRECTIONAL DRILLING TOOL Johns. Page, Sr., John S..Page,`Jr`., and Wade H. Antle, Long Beach, and'Floy'dB. Knickerbocker, Ventura, Salif., lassigner-stu Directional YEngineering Company, Long Beach, Calif., a corporation of California Application vMay 2, 1955, Serial` No. 505,192

4 Claims. V(Cl. Z55-i116) This invention has to do with a directional' drilling Itool for 'use in wells, and particularlyrelates' to' a tool for controlling the direction of the bore of`a well vsuch as an oil Well. It isa general object of thisinvention toV pro- Vide'a device whereby maximumpenetration' is possible while the direction ofkthe drilling 'is e'iect'ively controlled.

Ordinary well-drilling methods employ Vdevices in the nature of Wedges in order to deect a drilling 'string in the desired direction, the most common method being known as whipstocking These ordinary-methods require the lowering of a wedge or whipstock into the Well, that is oriented and which is then used to deect av bit of reduced size. Only a short amount of hole is made after which the entire drilling string `and whipstock are removed from the well and replaced by a new 'drilling string and bit that is used to bring the hole out'to gauge. fthe entire drilling string is again removed' andthe above process repeated. The ordinary methods areobviously time consuming and are, therefore, costly operations.

An object of this invention vis to` provide a directional drilling tool that is not limited to a single operation-in the well, but a tool which can be repeatedly operated as many times as desired.

Another object of this invention is to provide a simple hydraulicallyy operated tool responsive to iiuid pressures in the drill string and which may be operated regardless of movement of the tool-in the well. That is, theV tool may be rotated and/or reciprocated without affecting operation of the tool. The tool is controlled by the application of varying mud-pump pressures.

Still another object of `this invention is to provide a directional drilling tool as above referred to which employs hydraulically actuated Aguide shoes that are shiftable laterally into guiding engagement with thewall of the well. The guide shoes are yieldin'gly urged into pressure engagement with either the interior of a casing or the like, or with the interior wall of the well boreforrned by the earth formation, as the case may be.

It is another object of this invention to provide a hydraulically actuated means, as above referred to, with a hydraulic pressure boosting means that increases the effective holding power of the guide shoes above referred to so that the body or frame of the tool will .not rotate relative to the well as the drilling string and bit rotate and operate to extend the well.

lt is still another object of this invention to provide a directional drilling tool of the character referred to with return means that hydraulically retract the guide shoes so that Ythe structure is readily removable from the Well.

Further, an object of this invention is to provide a tool of the character above referred to with means for delaying action of certain parts of the structure so that rotation of the drilling bit precedes action of the tool softhat the bit may be brought into drilling contact with the casing or earth formation before lateral 'pressure' is'applied ln order to gain further deliection of the Well,

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2 thereto. Such action prevents''damageV to the bit'an'd'is highly useful in connection with the operation of diamond-'headed' bits.

The various objects and features of our invention will befully understood from the following detailed description of a typical preferred 'form and application of our invention, throughout 'which description reference is made to the accompanying drawings, in which:

Figs. 1 to '4 of the drawings illustrate the directional drilling tool that we have provided, Fig. 1 showing'the tool Vin the condition'to enterinto or be retracted from a well, Fig. 2 showing the tool after it khas been lowered to the desired operating position andwhere' the uppermost guiding meanshave been operated to` shift the tool laterally to one'side of the well, Fig. 3 being a View similar lto Fig. 2 showing the tool positioned'on an axis angularly related to the axis of the well as a result of lateralA shifting 0f`the lowermost guiding means which shifts the lower'end of the'tool to the other side of `the `well bore, and Fig. 4 being a view showing the condition of the tool after it has been operated'to extend the well bore so that itis'deiiected laterally at an' angle to the original well bore. Figs. 5 and 6 are enlarged detailed transverse sectionalviews takenas indicated by 5-5 and 6-6 on Fig. 3. Figs. 7 and 7a are longitudinal sectional views' showingthe construction'of the tool in the condition that it Vvappearsin Fig. l of the drawings. Figs. 8 and 8a are views similar to Figs. 7 and 7a respectively showingthe'tool in the condition which it appears in Figs. 3 and 4'of the drawings. ig. 9 is an enlarged 'detailed transverse'sectionalView taken as indicated by line 9-9`on Fig. 7. Fig. l0 is an enlarged detailedl sectional view taken as' indicated by line 1li-10 on Fig. v7. Figs. 1l to '13 are 'enlarged' detailed transverse sectional views taken as indicated by linesll-lL i12-12, and 13--13 on Fig. 7. r`Fig.l14 is an enlarged detailed transverse sectional'view taken as indicated by line 14--14 on Fig. 7a. Fig. l5 is anenlarged detailed sectional View taken as indicated byline 'l5-15 on"Fig. 8a. Figs. 16, 17, and 18 are'perspective views of the releasable drive means of the structure. Fig.- 19 is an enlarged 4detailed sectional view of a portion ofthe structure taken as indicated by line 19-19 on Fig. 14, and Figj20 is an enlarged longitudinal sectional View of a portion of the structurey illustrating'the double-actingfsealing means which we have provided between the reciprocating parts.

The directional drilling'v tool andthe method of operating the same* is illustrated in Figs. 1 to 4 of the drawings wherein the basicsteps involved'in the operation of the tool are shown. Fig. l'is a longitudinal vertical sectional view of atypical well at any point between" the top and bottom thereof-and theftoolX of the present invention isshown in a going in or going out condition in which' case the well or bore engaging elements arel retracted. Fig. 2 is a longitudinal vertical sectional View of a well showing thelower terminal end thereof which may be 'establishedbya' plug and showing the tool X after it has been rotatably oriented and the upperV end portion of the'` tool operated into engagement with one side wallof the well and rotation of the tool started. Fig. 3 is similar to Fig. 2 showingthe lower end portion of the toolV X operated into' engagement with the other side wall of the well and the bit'lowered into drilling engagementwith'the plug closing' the well. Fig. 4 is similar to Fig. 3 showing thecondition of the well after the tool'X'has progressed"downwardly'to divert or de-` iiect the vbore of thewell toI lone side -of theoriginal'well or casing. Y A

TheA directional drilling tool1 *X that we have provided is adapted tofcontroladrillingl'bit'T;to dee'ct'a Well W` and is insertedinadrilling" string"Si-betWeen' the'ibit'y T and the 'drillpipe i0, preferably at the lowermo'st'4 end of the drilling string S. The tool X is useful in connection with the rotary drilling method of digging wells in which method hydraulic fluid is handled by the drilling string S. The fluid is pumped into the string S at rather high pressures during operation of the string S and it is this fluid under pressure that we employ to actuate the movable elements of our tool.

lt will be apparent from Figs. l to 4 of the drawings that the drilling string S is positioned at one side of the well W, so that the lower end portion of the string S and the bit T are angularly related to the central axis of the well. By angularly relating the axis of the drilling string S to the axis of the well W it will be apparent that the drilling bit will advance downwardly at an angle to the existing axis of the well.

The bit T may be any suitable drilling bit such as a rock drilling roller bit or may be a diamond headed drilling bit as shown. In the case illustrated where the well is to be deflected through the side of a casing R it is preferred that a diomand headed bit T or the like be employed. The bit T illustrated in the drawings has a head 11 of a diameter that forms a well bore of the desired diameter and a threaded pin 12 for coupling the bit T to the lower end of the drilling string. The head 11 is impregnated with or carries cutting elements such as diamonds so that as the bit is rotated and downward pressure applied thereto it advances downwardly to extend the well W. A fluid ow restricting orifice 13 is carried in the bit body so that hydraulic pressure can be built up by increasing the supply of fluid to the string 8.

The directional drilling tool X involves generally a drive shaft A adapted to be inserted in the drilling string S between the bit T and drill collar or pipe 10, a body B engaged over and surrounding the drive shaft A, a head C at the upper end of the body B and rotably carried on the drive shaft A, a head D at the lower end of the body B and rotatably carried on the drive shaft A, means E rotatably coupling the drive shaft A and head C, means F releasably driving the body B from the drive shaft A, guide means G at the head C and operable into engagement with the wall of the well, guide means H at the head D and operable into engagement with the wall of the well, hydraulic operating means J for actuating the guide means G, hydraulic operating means K for actuating the guide means H, and various other features of construction as hereinafter described.

The drive shaft A is an elongate tubular element that is inserted in the drilling string S between the drill pipe 1i? and the bit T, and is characterized by a circular wall 15 having a smooth outer surface 14 and a central ow passage 16 extending therethrough from one end to the other and opening at the top and the bottom of the drive shaft. The drive shaft A is preferably sectional in order to facilitate assembly of the other parts and elements of the structure, there being upper and lower sections Y and Z joined by a coupler 17. The upper and lower sections are threaded at 18 and 19 respectively and the coupler 17 is a sleeve-like part engaged over the end portions of the sections and threadedly joined thereto. The inner ends Y and Z of the sections are juxtapositioned, as shown.

The drive shaft A is provided with couplings 2U and 21 at the upper and lower ends thereof which couplings are in the nature of enlargements at the ends of the drive shaft. The coupling 20 is at the upper end of the upper section of the shaft A and is integral therewith and has a box-type end portion with internal threads adapted to receive the lowermost section of the drill collar or pipe 10. The coupling 21 is at the lower end of the lower section of shaft A and is integral therewith and having a box-type end portion with internal threads adapted to receive the pin 12 projecting upwardly from the bit T.

The body B is preferably an elongated cylindrical element that is engaged over and surrounds the drive shaft A. In accordance with the invention the body B is rotatably carried on the shaft A in a fixed position axially thereof through the heads C and D later described. The body B is characterized by an outer cylindrical wall 25 that surrounds the wall 15 of the shaft A leaving an annulus between the inner surface 26 of the wall 25 and the outer surface 14 of the wall 15. The outer surface 27 of the wall 25 is preferably smooth and uninterrupted throughout the length of the body B.

The head C may be joined to the upper end of the body B by means of a threaded connection 30 and is an elongate part that is rotatable on the cylindrical outer surface 14 of shaft A, and incorporates the means E above referred to and carries the guide means G, which means are hereinafter described. The head C has a cylindrical bore 31 terminating at a lower end face 32 and has a cylindrical outer surface 33 which is a continuation of the outer surface 27 of the body B. Bore 31 is concentric with and spaced from the outer surface 14 of shaft A leaving an annular space therebetween. A counterbore 34 enters the upper end of the head C where suitable packing rings 35 are carried. For example, chevron packing rings may be employed and faced in opposite directions so that ow of fluid between the parts is checked in either direction.

The head D may be joined to the lower end of the body B by means of a threaded connection 36 and is an elongate part that rotatably engages the cylindrical outer surface 14 of the shaft and carries the guide means H hereinafter described. The head D has a cylindrical bore 37 terminating at an upper end face 38 and has a cylindrical outer surface 39 which is a continuation of the outer surface 27 of the body B. Bore 37 is concentric with and spaced from the outer surface 14 of shaft A leaving an annular space therebetween. A counterbore 40 enters the lower end of the head D where there is a bearing 41 and suitable packing rings 42 oppositely faced in order to check the flow of fluid in either direction. A retainer 43 is threaded onto the head D to hold the packing rings 42 and bearing 41 in working position. The bearing 41 is carried in the counterbore 40 above the packing rings 42 and may be a sleeve of anti-friction material slidably engaged with the smooth outer surface 14 of the shaft A. There is preferably a bearing surface 44 of enlarged diameter on the exterior of the shaft A at the lower end portion thereof to slidably engage in the bearing sleeve 41.

The means E rotatably coupling the shaft A and head C is incorporated in the head C and involves generally a radially outwardly projecting abutment ring 45 carried on the shaft A and upper and lower bearing rings 46 and 47 between the shaft A and head C and engaged with the abutment ring 45 to prevent axial movement of the shaft A and head C relative to each other. In the case illustrated, the lower bearing ring 47 is shown as an anti-friction ball bearing ring. A recess 48 is provided in the upper end of the head C and enters the head to terminate at an upwardly facing shoulder 49. A spacer ring 47 is provided to occur between the shoulder 49 and the bearing ring 47 to support the ring 47 in the construction. The ring 47 seats on the spacer ring 47 and operates against the lower sides of the abutment ring 45. The ring 46 is carried above the abutment ring 45 and operates against the upper side thereof. The abutment ring 4S is threadedly carried on the shaft A and has flat faces 50 in planes normal to the longitudinal axis of the tool and which engage the rings 46 and 47. A retainer 51 is threaded onto the head C and is provided with a downwardly facing seat 52 engageable with the ring 46. Wiper rings 53 are carried by the retainer 51 to exclude foreign material from the interior of the tool.

The means F releasably driving the body B from the drive shaft A is provided for rotatably orienting the tool X in the well before or between drilling operations, and involves generally, a driving member 55 on the shaft A, a driven member 56 on the body B, and a coupler 57 shiftable into engagement with the members 55 and S6 afssmsa to connect said members. The driving member. 55 isca'rried on the shaft A midway between 'the ends' thereof and below the hydraulic operaingmea'ns J, to-be'- operated thereby. The driving member 55, clearly'shown inl Figs. 7 and 18 of the drawingspis-preferably formed integrally with the coupler 17 at the upper end thereof and involves jaw 58 extending circumferentially ofthe upper end portion of the coupler 17.

The driven member 56, clearly shown in Figs. 7 and 17 of the drawings, is a sleeve-like part that surrounds the upper end portion of the coupler-17 and is provided with jaw 59 extending circumferentially-of the -upper end portion thereof. The driven member 56fsurrounds ythe driving member 55 and is secured to the wall 25of the body B by means of fasteners60, as shown -in Fig. 7. The jaws 5S and 59 are alike and may' include several circumferentially spaced, upwardly projecting tooth-shaped elements, the form and circumferentially positioning of the teeth being such that the jaws will vregister'onlyl at one point of rotation of the shaft A relative to the body B.

The coupler 57, clearlyshown in Figs. 7 and 16 of the drawings, is shiftably carried inthe annulusbetween the shaft A and body -B and' is movable vertically into and out of engagement with the jaws 58 and 59. The coupler 57 is a ring-shaped part that surrounds the shaft A and has dog 61 shaped-to t into or between the jaws S8 and 59 to couple them together thereby rotatably joining the shaft A and body B. As shown, the coupler 57 is operated bythe movable 'element' or piston-'100 of the hydraulic operating means L'hereinafter described, and is guided by a pin 62 carried by the fbody'an'd operable in a guideway 63 inthe' exterior of the'said piston of the means I. In the case-illustrated, the coupler-'is attached to the piston in fixed relationship thereto by-means of a suitable pin 57. The guideway 63 extends vertically and the pin 62 operates to rotatably position the coupling member S7 so that it meshes `with thedriven member 56 which is iixed to and is carried'by the body.

The guide means G atthe upperend of the -tool.or at the head C is adapted to beoperated into pressure engagement with the wall ofthe well and involves `generally a plurality of xed guide shoes 65, a` plurality of shiftable guide shoes 66, and a hydraulic actuating means 67 for the guide shoes 66. The .guide means G operates to yieldingly urge the upper end of tool 'XY into-pressure engagement with one sideof the wellcasing vorl well bore, for example, the left hand side as shown, and involves one or more shoes l65 and shoes'66. In the preferred form of the invention there are'two shoes 65' and two shoes 66 all equally spaced circumferentially of the head C and 90 apart with the shoes 65 at one side of the tool X and the shoes 66 at the other sideofthe tool X as clearly illustrated in Fig. 5`of the drawings.

The fixed guide shoes 65 are vertically disposed parts iixedly carried in recesses 66 in thel outer surface 33 of the head C-and each is characterized by a vertically disposed guide or runner 68. The guide Vor runner 68 projects radially of the tool and is provided with a sharpened edge that engages with the wall of the'casing or well bore, as the case may be.

The live guide shoes 66 are'vertically disposed parts shiftably carried at the exterior of the head' C and each is characterized by a vertically disposedguide on runner 70. The guide or runner 70 projects radially of the tool and is provided with a sharpened edgeengageable with the wall of the casing or well tbore, as thecaseV may be.

The hydraulic actuating means -67 for theilive guide shoes 66 may vary in form as circumstances require and in the preferred form of the invention, each guide shoe 66 is individually actuated by a pair of vertically spaced hydraulic actuators 71, see Fig. l0. Theactuators 71 pivotally carry the end portions of the shoe 66 and each involves a cylinder 72, a piston 73,' and a connecting pin 74. The cylinder 72 is preferably'a separate machined part threaded intoa lateralbore75 that extends transversely of the head C between the outer-"surface 33 and annulus between the shaft A and head C. The axes'v of the cylinders 72 are spaced and parallel and are normal to the central vertical axis of the tool X, and each has a cylinder opening 76 and is provided with fa head 77 at the outer end thereof carrying a seal 78.

The piston 73 Iis slidably carried in the cylinder opening 76 and projects through the head 77 to connect with the guide shoe 66. lA flange 79 is carried on the inner end ofthe piston 73 to limit lateral or outward movement of the piston. Circumferentially spaced ats 80 are provided about the ilange 79 to allow for free ow of fluid around the piston 73. When pressure occurs in the annulus above referred to, the fluid operates to force the piston 73 outwardly through the head 77. The connecting pin 74 is carried at the outer end of the piston 73 on an axis normal to the axis of the pistonand extending transversely of the tool-X. The connecting pin'7f'l projects from the sides of the piston 73 to engage in openings 82 in the guide shoe 66. It will be apparent that transverse or lateral movement of the pistons 73 will operate the guide shoes 66 so that they 'move inwardly or outwardly relative to the body B and head C of the tool.

The guide means H at the lower end of the tool-or at the headD (see Fig. l5) is adapted to be operated into pressure engagement with the wall of the well casing or Well boreand involves generally a plurality of ixed guide shoes 85, a plurality or" shiftable or live guide shoes 86, and hydraulic actuating means 87 for the shoe 86. The guide l meansv H operates to yieldingly urge the lower end of the tool X into pressure engagement with the side of the' well casing -or -well bore-opposite that which is engaged by the upper end of the tool. For example, -the right hand side of the well as shown.v The guide means H involves one or more-of the-'shoes 85 and shoes -86 likeand corresponding to the shoes 65 and 66 above de` scribed. The shoes 8S and86 may be `identical-to the shoes-65 and 66 aboverefe'rred to, the fixed shoes-85 being carried in vertically disposed recesses '86 in the outer surface 39 of the head D. Each shoe 85 has a vertically disposed guide or runner 88 that projects radially from the tool to present a sharpened edge engageable with the wall of the well casing or well bore. The live guide shoes 86 are shiftably carried at the exterior of the head D and each has a vertically disposed guide or runner 90.

The hydraulic actuating means 87 may be identical with the means 67 above described and are provided to actuate the live shoes S6, each shoe 86 being individually actuated by spaced actuators 91. Each actuator 91 involves a cylinder 92, a piston 93, and a connecting pin 94 corresponding to the cylinder 72, piston 73, and pin 74 above described.

The hydraulic operating means I for actuating the guide means G at the head C operates to actuate the hydraulic actuating means 67 and is a cylinder and piston mechanism responsive to pressure of fluid in the string S and delivers fluid pressure to the hydraulic actuators 67. The hydraulic operating means I involves an annular piston 108 carried in the annulus between the outer surface 14 of shaft A and the inner surface 26 of body B. The piston is slidably carried between the shaft A andy body B and has an inner wall 101 slidably carried on the wall 15v and an outer wall 102 slidably carried within the wall 25. The pin 62 carried by the body B and engaged in the guideway 63 in the piston, as above described, prevents relative rotation between the piston and the body. The inner wall 101 is coextensive with the piston 100 while the outer wall 102 extends along the lower end portion thereof so that the lower end of the piston 100 completely occupies the annulus. The upper end portion of piston 109 is of reduced diameter `forming a'ram 103 of smaller diameter than the lower end portion'of the piston. The `rain. 103 slidably enters a counterbore 104 in the bore 31 and enters the head C at the lower end face 32. Seals 195 and 106 are provided in the head C and piston 100 respectively and packing rings 107, for example, chevron packing rings are carried by the piston to prevent the ilow of fluid in either direction between the piston Al@ and the outer surface li of the shaft A.

In accordance with the invention, the coupler 57 of the means F hereinabove described is carried by the piston lill) at the lower end thereof and in practice a retainer 108 secures the rings 107 in Working position and the coupler 57 is carried by the retainer 163 and is preferably formed integrally therewith. in the preferred carrying out of the invention, the pin 57 attaching the coupler 53 to the piston ith@ is carried by the piston and engages in a suitable opening provided in the retainer M36 on the piston.

A pair of uid handling ports il@ are provided in the shaft A below the hydraulic operating means l, and as shown, extends through the coupler i7 between the passage 16 and the annulus between the shaft A and body B. When fluid under pressure enters the annulus through the ports il@ it acts upon the lower or bottom end of the piston i@ and moves the piston upwardly, forcing the ram M3 on the piston upwardly into the counterbore 3104 thereby establishing uid pressure above the piston ll and which is applied to the actuators 7l. The piston l0@ is considerably larger in cross section than the ram 103, with the result that the uid pressure established above the ram and acting upon the actuators '7i is substantially greater than the fluid pressure acting upon the lower end of the piston.

The piston Mtl is returned or moved downwardly by means of a spring 111 that abuts the lower end face 32 of the head C and operates against a shoulder 112 on the piston Mtl. A breather opening M3 is provided in the wall of the body B to allow for free shifting of the piston lili) longitudinally of the tool. It will be apparent that as the spring lill returns the piston it) the pistons of the actuators 7i are drawn inwardly retracting the guide shoes 66.

The hydraulic operating means K for actuating the guide means H at the head D operates to actuate the hydraulic actuating means 87 and is a cylinder and piston mechanism responsive to pressure of huid in the string S and delivers uid under increased pressure to the hydraulic actuators 91. The hydraulic operating means K involves an annular piston 120 carried in the annulus between the outer surface lid of shaft A and the inner surface 25 of body B. The piston i2@ is slidably carried by the shaft A and body B and has an inner wall 121i slidably carried on the wall 15 and an outer wall 122 slidably carried within the wall 25. The wall 121 is coextensive with the piston i243 while the wall l2?. extends along the upper end portion thereof so that the upper end portion of the piston i2@ completely occupies the annulus. The lower end portion of piston l2@ is of reduced diameter forming a ram 323 of smaller diameter than the upper portion of the piston Tilt). The ram iZ slidably enters in a counterbore i124 in the bore 37 and enters the head D at the upper end face 38. Seals 125 and 126 are provided in the head D and piston l2@ respectively and packing rings 127, for example, chevron packing rings are employed to prevent the ow of fluid in either direction between the piston l2@ and shaft A. in practice, a retainer 325 secures the rings L26 in working position.

The uid handling ports il@ occurs above the piston 12.0, and when huid under pressure enters the annulus the piston Z moves downwardly forcing the ram 123 into the counterbore 24 thereby establishing increased fluid pressure below the piston l2@ and which is applied to the actuators 9i.

The piston 120 is returned or moved upwardly by means of a spring 131 that abuts the upper end face 38 of the head D and operates against a shoulder lt32 on the piston 120. A breather opening 133 is provided in the wall 25 of body B to allow for free movement of the piston longitudinally of the tool. It will be apparent that as the spring 131 returns the piston l2@ to the down position that the pistons of the actuators 91 are drawn inwardly thereby retracting the guide shoes 86.

It is a feature of the present invention that we have provided means for retarding movement of the piston of the hydraulic operating means K so that the means I and the upper guide means G are operated before the means K and the lower guide means H. As shown in Figs. 7au and 19 of the drawings, there is a flow controlling ring M0 carried in the counterbore l2@ at the lower end thereof and engageable with a seat 141 in the head D to seal therewith. The ring surrounds the shaft A with suitable clearance to form an annular orifice opening 142 and is free to shift or move upwardly on shaft A. A retainer ring 143 is suitably placed on the shaft A to limit upward movement of the ring 140. When fluid is urged downwardly by the ram 123 of means K the annular orifice formed by the ring 140 surrounding the shaft A limits the flow of uid so that movement of the guide means H into engagement with the well is retarded. However, when the tool is to be released the ring Mtl moves upwardly off of seat 141 allowing for free ow of fluid and consequent rapid movement.

From the foregoing, it will be apparent that we have provided an extremely simple and eective tool for directional well drilling. In order to operate the directional drilling tool of the present invention, it is merely necessary to apply it to the lower end of the drilling string S as above set forth and to reduce the mud pump pressure in the drilling string in order that the clutch means F is in locked position and the guide means G and H are retracted. With the guide means retracted the tool and string S may be lowered into the well and when the desired depth has been reached, preferably so that the bit T is spaced from the bottom of the well or the plug therein, the tool is rotatably oriented whereupon the mud pump pressure is increased. Increasing or building up the pressure of the mud in the drilling string S by forcing it through the orifice or restriction in the bit T causes pressure to develop within the string and tool X whereupon the means l and K operate to release the clutch means F and deliver increased uid pressure to the guide means G and H. In practice, the ratio of pressures developed may be about 4 to l so that the actuators 71 and 91 are moved laterally or outwardly into pressure engagement with the casing, or well wall. As above pointed out, the upper guide means operates more quickly than the lower guide means, the movement of the lower guide means being retarded by the orice formed by the ring tdt). T erefore, bit T may be advantageously rotated prior to engagement with the side of the well or casing in order to avoid damage thereto which might otherwise occur. In order to retract the tool from the well the mud pump pressure is reduced to a point where the springs Mil and 131 act to retract the pistons whereupon the guide means are drawn in to the retracted or unactuated positions and the clutch means F is re-engaged. in practice, the entire interior of the tool is packed with material such as hard grease so that the parts are protected and so that operation of the tool is uniform.

Having described only a typical preferred form and application of our invention, we do not wish to be limited or restricted to the specic details herein set forth, but wish to reserve to ourselves any variations or modifications that may appear to those skilled in the art and fall within the scope of the following claims.

Having described our invention, we claim:

l. A well drilling tool engageable in a iluid handling drilling string including, an elongate vertically disposed tubular iluid conducting drive shaft adapted to be inserted in the drilling string, an elongate tubular body engaged around the shaft, heads fixed to the upper and lower ends of the body, bearing means rotatably coupling the heads and the shaft and holding them against relative axial movement, guide means carried by the heads and each including a guide shoe adapted to be shifted laterally into pressure engagement with the Wall of the well, the shoes carried by the rupper and lower heads occurring at circumferentially spaced sides of the tool, hydraulic actuating means for the shoe in each head, said actuating means including lradially shiftable piston units carried by the heads and coupled to the shoes and 4responsive to fluid pressure in the string and drive shaft, and means releasably driving the body from the shaft `and including a driven member on the body and a drive member on the shaft, a longitudinally shiftable piston surrounding the drive shaft and responsive to fiuid pressure in the shaft and means carried by the piston and operatively related to the drive and driven members t make and break the drive therebetween upon longitudinal shifting of the piston.

2. A well drilling tool engageable in a fiuid handling drilling string and including, an elongate vertically disposed tubuar fluid conducting drive shaft adapted to be inserted in the drilling string, an elongate tubular body engaged around the shaft, heads having central longitudinal bores fixed to the upper and lower ends of the body, bearing means rotatably coupling the heads and the shaft and holding them against relative axial movement, guide means carried by the heads and each including a fixed guide shoe and a movable guide shoe spaced circumferentially from the fixed shoe and adapted to be shifted laterally into pressure engagement with the wall of the well, the fixed and movable shoes carried by the upper and lower heads occurring at circumferentially spaced sides of the tool, respectively, hydraulic actuating means for the movable shoe in each head, said actuating means including radially shiftable piston units carried by the heads and coupled to the shoes, operating means adapted to deliver iiuid under pressure to the actuating means and including a longitudinally shiftable piston for each actuating means and carried in the body, a counterbore in each head establishing a passageway communicating with the piston unit therein, a ram carried by each piston and shiftably engaged in the counterbores in the heads to urge the fluid in the counterbores into the piston units, and a port conducting fluid from within the drive shaft to the pistons, the rams of the operating means being of smaller cross section than the pistons whereby the pressure exerted on the piston units is greater than that exerted on the pistons, and means releasably driving the body from the shaft and including a jaw on the body, a jaw on the shaft and a coupler carried oy one of the pistons of the operating means and shiftable into and out of engagement with the jaws.

3. A well drilling tool engageable in a fluid handling drilling string including, an elongate vertically disposed tubuar fiuid conducting drive shaft adapted to be inserted in the drilling string, an elongate tubular body engaged around the shaft, heads fixed to the upper and lower ends of the body, bearing means rotatably coupling the heads and the shaft and holding them against relative axial movement, guide means carried by the heads and each including a guide shoe adapted to be shifted later-ally into pressure engagement with the wall of the well, the shoes carried by the upper and lower heads occurring at circumferentially spaced sides of the tool,y

hydraulic actuating means for the shoe in each head, said actuating means including radially shiftable piston units carried by the heads and coupled to the shoes and responsive to uid pressure in the string and drive shaft, and means releasably driving the body from the shaft and including a driven member on the body and a drive member on the shaft, said members having circumferentially spaced parts adapted to register when the body and shaft are in a predetermined relative rotative position, a longitudinally shiftable piston surrounding the drive shaft and responsive to fuid pressure in the shaft and means carried by the piston and operatively related to the drive and driven members to make and break the drive between the parts on the members when the parts are in register and upon longitudinal shifting of the piston.

4. A well drilling tool engageable in a fluid handling drilling string and including, an elongate vertically disposed tubular iiuid conducting drive shaft adapted to be inserted in the drilling string, an elongate tubular body engaged yaround the shaft, heads having central longitudinal bores xed to the upper and lower ends of the body, bearing means rotatably coupling the heads and the shaft and holding them against relative axial movement, guide means carried by the heads and each including a fixed guide shoe and a movable guide shoe spaced circumferentially from the xed shoe and adapted to be shifted laterally into pressure engagement with the wall of the well, the fixed and movable shoes carried by the upper `and lower heads occurring at circumferentially spaced sides of the tool, respectively, hydraulic actuating means for the movable shoe in each head, said actuating means including radially shiftable piston units carried by the heads and coupled to the shoes, operating means adapted to deliver fluid under pressure to the actuating means and including a longitudinally shiftable piston for each actuating means and carried in the body, a counterbore in each head establishing a passageway communicating with the piston unit therein, a ram carried by each piston and shftably engaged in the counterbores in the heads to urge iiuid in the counterbores into the piston units, and a port conducting fluid from within the drive shaft to the pistons, the rams of the operating means being of smaller cross section than the pistons whereby the pressure exerted on the piston units is greater than that exerted on the pistons, and means releasably driving the body from the shaft and including a driven member with a longitudinally disposed jaw on the body, a drive member with a longitudinally disposed jaw on the shaft, said jaws registering when the body and shaft are in a predetermined relative rotative position and a coupler carried by one of the pistons of the operating means and shiftable into and out of engagement with the jaws when the jaws are in register.

References Cited in the file of this patent UNITED STATES PATENTS 2,061,316 Brack et al. Nov. 17, 1936 2,119,095 Brumrnett May 31, 1938 2,173,309 Monroe Sept. 19, 1939 2,316,409 Downing Apr. 13, 1943 2,319,236 Isaacks et al. May 18, 1943 2,329,597 Diehl Sept. 14, 1943 2,658,459 Page Nov. 10, 1953 2,674,313 Chambers Apr. 6, 1954 2,745,635 Zublin May 15, 1956 2,796,234 Mann June 18, 1957 

